Prognostic significances of tumor-infiltrating S-100 positive dendritic cells and lymphocytes in patients with hepatocellular carcinoma

Background/Aims: To investigate the prognostic significances of dendritic cells and lymphocytes infiltration in hepatocellular carcinoma Methodology: The clinicopathological and follow-up data of 44 patients with hepatocellular carcinoma, who underwent curative resection of tumor in our hospital from January, 1995 to July 1996, were collected. Immunohistochemical staining was employed to detect the S-100 positive dendritic cells in the tumor tissue, and lymphocytes infiltration was evaluated simultaneously. The relationship of the tumor-infiltrating dendritic cells and lymphocytes to the postoperative recurrence-free time and survival rate was analyzed. Results: Either the tumor-infiltrating dendritic cells or the tumor-infiltrating lymphocytes alone had no significant relationship to the postoperative recurrence-free time and survival rate. By taking into consideration both tumor-infiltrating dendritic cells and lymphocytes simultaneously, the patients were classified into two groups. Group A included patients having dendritic cell counts greater than or equal to20 cells/10 high power fields together with positive lymphocytes infiltration (n=17), and group B consisted of patients having dendritic cell count greater than or equal to20 cells/10 high power fields but with negative lymphocytes infiltration or dendritic cell count greater than or equal to20 cells/10 high power fields with either positive or negative lymphocytes infiltration (n=27). There were no significant differences in clinicopathological features between two groups. The recurrence-free tune was markedly longer in group A as compared with group B, with a median time of 21.6 months for group A and 4.1 months for group B (P<0.05). The 1-, 3-, 4-year survival rates were significantly greater in group A than those in group B, being 83.5% vs. 42.2%, 61.8% vs. 28.4% and 48.7% vs. 23.0%, respectively (P<0.01). Conclusions: Marked infiltration of dendritic cells together with lymphocytes in tumor tissue was closely related to the improved clinical prognosis in patients with hepatocellular carcinoma, and represented as an independent prognostic factor.